Knockdown ramp construction

ABSTRACT

A knockdown ramp construction has a plurality of quadrangular platform members of uniform length, width, and height arranged in adjacent stacks of different heights. Vertically adjacent platform members are coupled to one another by removable couplers which preclude relative horizontal movement between adjacent platform members. An inclined riser member atop the uppermost platform member of each stack provides a smoothly inclined upper surface for the ramp. Separable connectors connect adjacent stacks of platform and riser members to one another, thereby precluding relative movement of the stacked members in directions away from one another.

[0001] This invention relates to a knockdown ramp construction composed of a plurality of uniform platform and riser members removably connected to one another to form a smooth, inclined surface between two different levels.

BACKGROUND OF THE INVENTION

[0002] There are many instances in which a temporary ramp is desirable to facilitate transition from one elevation to another. For example, a ramp to facilitate movement of a wheeled object, such as a wheel chair, between different levels is desirable in those instances in which the need for the wheeled object is temporary. Many temporary ramp constructions have been proposed, but not all of them have been satisfactory for a number of reasons. For example, it is not uncommon for the known ramp constructions to be composed of a fairly large number of different size and different shape components, thereby requiring considerable skill in forming and assembling the components to construct a suitable ramp. In addition, it is not uncommon for the components of a ramp to become separated from one another fairly easily, thereby resulting in unacceptable instability of the ramp.

[0003] An object of the invention is to provide a knockdown ramp construction which overcomes the disadvantages referred to above.

SUMMARY OF THE INVENTION

[0004] A ramp constructed in accordance with the invention is composed of relatively few, modular components which are usable to form ramps of virtually any length and height and composed of components which provide rigidity and stability for the completed ramp. The components comprise uniform platform members and uniform riser members, the platform members having substantially planer, parallel upper and lower surfaces and the riser members having planar lower surfaces and upper inclined surfaces which rise a distance corresponding to the thickness or height of a platform member.

[0005] The platform members are vertically stackable and are stabilized against relative lateral movement by coupling members. The riser members correspond in width to that of each platform member and may be connected to an underlying platform member by coupling members of the same kind used to join vertically adjacent platform members.

[0006] The lowermost platform member of each stack of platform members may be connected to the lowermost member of an adjacent stack by a connector which prevents relative movement of adjacent stacks in a direction away from one another.

[0007] The uppermost platform member at the higher end of the ramp may be topped by an uppermost riser member and the shorter end of the ramp may be constituted by one of the riser members. It thus is possible to provide a ramp having a smoothly inclined surface from one end of the ramp to the other.

[0008] Although the riser members have a width corresponding to that of each of the platform members, the length of a riser member may be either the same as or less than that of a platform member. This makes it possible to provide a ramp having considerable lateral stability, but minimizes the width of the inclined surface to that which is needed.

[0009] Each of the platform members is of uniform thickness and the upper and lower horizontal surfaces thereof are joined by smooth, vertical side and end walls of uniform thickness. The platform members therefore can be positioned one atop another to form a stack of selected height. To prevent inadvertent lateral movement of adjacent platform members separable coupling members are provided which include sockets in the lower surface of each platform member and comprise a generally cylindrical body capable of removable accommodation in a socket in the lower surface of an upper platform member, the body terminating at its opposite end in lugs which interlock with cross bars provided in the upper surface of the adjacent lower platform member thereby providing security against relative lateral movement of vertically adjacent platforms.

[0010] The lowermost platform members of adjacent stacks are connected to one another in such manner as to prevent movement of one stack relative to another in a direction that would separate the adjacent stacks. The connector includes a base above which retainer fingers project, the fingers being spaced from one another a distance corresponding to twice the thickness of a vertical wall of the platform members. The arrangement is such that, when the side or end walls of two adjacent platform members abut one another, the fingers of the connector will straddle the two walls and restrain the platform members against separation.

[0011] Each riser member is of wedge configuration and has a lower, horizontal surface and an inclined upper surface. The inclination of the upper surface is such that, at the thicker edge of the riser, there is a vertical wall which corresponds in height and thickness to a sidewall of a platform member. Thus, when a riser member is placed atop a platform member there will be a smooth, inclined surface from that edge of the riser which abuts the platform to the opposite edge of the riser.

[0012] The riser members may be secured to underlying platform members by the same couplings that are used to secure vertically stacked platform members to one another. Further, the same connectors that are used to prevent adjacent stacks of platform members from separating may be used to prevent a riser member forming the lower end of a ramp from separating from the adjacent platform member.

[0013] Since all of the platform members are uniform and all of the riser members are uniform, and since all of the vertical coupling members are uniform and all of the lateral connectors are uniform, only four different kinds of components are required to construct a ramp of any desired height and length. Since all of the couplings and connectors are removable and since all of the platform and riser members are independent of one another, a ramp can be erected and dismantled very easily and quickly.

[0014] The parts from which a ramp is constructed preferably are molded from suitable plastic materials and are so constructed as to be light in weight and structurally stable.

THE DRAWINGS

[0015] Apparatus constructed in accordance with the preferred embodiment of the invention is illustrated in the accompanying drawings wherein:

[0016]FIG. 1 is an exploded, isometric view illustrating the manner in which a typical ramp may be constructed;

[0017]FIG. 2 is an isometric, partly exploded view showing a virtually completed ramp;

[0018]FIG. 3 is an enlarged, isometric, exploded view of a platform member and a riser member illustrating the manner in which they removably may be coupled to one another;

[0019]FIG. 3A is a fragmentary view of two of the components shown in FIG. 3, but in inverted positions;

[0020]FIG. 4 is an enlarged vertical sectional view of a portion of a ramp and illustrating how a riser member and a platform member may be connected to prevent movement of such members away from one another;

[0021]FIG. 5 is a isometric, enlarged view of the connector shown in FIG. 4; and

[0022]FIG. 6 is a top plan view of the connector shown in FIG. 5.

DETAILED DESCRIPTION

[0023] A ramp constructed in accordance with the preferred embodiment of the invention is designated generally by the reference character 1 in FIG. 2 and is composed of a plurality of identical quadrangular platform members 2, a plurality of identical wedge shaped riser members 3, a plurality of identical vertical couplers 4, and a plurality of identical horizontal connectors 5.

[0024] As is best shown in FIGS. 1 and 3 each platform member 2 is quadrangular and has a plurality of longitudinally and transversely extending, interconnected ribs 6 and 7, respectively, which form a grid having a plurality of spaces 8 therein. At opposite sides of each platform 2 are vertical side walls 9 and at opposite ends of each platform member are end walls 9 a. The walls 9 and 9 a are perpendicular to the upper and lower surfaces of the platform members. The height and thickness of each wall 9 and 9 a are identical. Except as is set forth subsequently, each of the ribs 6 and 7 and each of the walls 9, 9 a are uniform in height.

[0025] At suitably spaced intervals each platform has a cylindrical socket 10 having a smooth bore and an annular wall 11. Adjacent the upper surface of each platform member the ribs 6 and 7 span the sockets 10, but those ribs 6 and 7 which span the sockets are of reduced height so as to enable each socket to be open and unobstructed at the lower surface of each platform 2. The location of the sockets is such that the sockets in one platform are vertically aligned with the sockets in vertically adjacent platforms.

[0026] As thus far described, the platforms 2 correspond to the platforms shown in U.S. Pat. No. 5,683,004.

[0027] Each of the riser members 3 is identical and has a smooth upper surface 12 terminating at one edge in a side wall 13 and at its opposite ends in end walls 13 a. The walls 13, 13 a are perpendicular to the lower surface of the riser member. The thickness of the walls 13, 13 a corresponds to that of the walls 9, 9 a of the platforms 2. The surface 12 is supported from below by longitudinally and transversely extending ribs 14 and 15, respectively, which form spaces 16. As is shown in FIG. 3A, the ribs 14 extend the full length of the riser member 3 but the ribs 15 extend only about half the width of the riser. At suitably spaced intervals sockets 17 are formed by an annular wall 18, and each such socket corresponds to the size and spacing of the sockets 10 which extend alongside one of the walls 9 of the platform 2.

[0028] The couplings 4 correspond to those disclosed in U.S. Pat. No. 5,683,004 and each coupling comprises an annular body or insert 19 of such size as removably and snugly to be accommodated in any one of the sockets 10 and 17. The body 19 is open at one end and, at its other end, has a wall supporting a pair of spaced lugs projections 20 each of which is provided with a shoulder 21. The space between the projections 20 is sufficient to accommodate the rib 6 which traverses a socket 10 and the projections 20 are of such size as to enter the spaces on opposite sides of the rib 6. When two of the couplings 4 are accommodated in two of the sockets of either of the members 2 or 3, the couplings restrain relative movement horizontally between such members.

[0029] The apparatus thus far described makes it possible to construct a ramp 1 wherein a plurality of platform members 2 are arranged in vertically ascending stacks adjacent one another with each adjacent stack having a height different from the next adjacent stack. In the ramp shown in FIG. 2, there is one platform 2 at the lower end of the ramp, two stacked platforms adjacent the single platform, three stacked platforms 2 adjacent the pair of stacked ramps, and four platforms 2 at the higher end of the ramp. Positioned atop the uppermost platform 2 in each stack is a riser member 3. Adjacent the lower end of the ramp is a single riser member 3. In the ramp shown in FIG. 2 each of the platform members 2 is of uniform length, width, and height and each of the riser members corresponds to the length and width of each platform member. However, since each riser member is of wedge configuration it has only one side wall 13 which extends the full length of the riser and has a height corresponding to the height of the side wall 9 of the adjacent ramp member. The surface 12 of the riser is inclined at such an angle to the horizontal as to provide a smoothly inclined surface from one end of the ramp to the other.

[0030] Each of the stacks of platform and riser members is stable in all horizontal directions because of the coupling members 4 which couple the stacked platform members to one another and the riser members to the uppermost platform member of each stack. However, each stack of such members could move transversely relative to one another since none of the couplings 4 connects any of the platform members or riser members to corresponding members of adjacent stacks. The ability of adjacent stacks of members to move transversely relative to one another is overcome by the provision of the connectors 5.

[0031] Each connector 5 comprises a base 22 having two pairs of upstanding retainer fingers 23 and 24. Between each pair of fingers 23 and 24 is a space 25 which is twice the thickness of each wall 9 and 13 of each platform 2 and riser 3, respectively. This spacing makes it possible for any two adjacent walls 9 of two ramp members 2 or any two adjacent walls 9 and 13 of adjacent ramp members 2 and riser members 3 to be accommodated snugly in the space 25 and thereby enable adjacent platforms and risers to be restrained against relative horizontal movement.

[0032] The walls 9 and 9 a of the platform members 2 are provided with notches 27 and the walls 13 and 13 a of the riser members 3 are provided with similar notches 28 along their lower edges of such depth as to accommodate the base 22 of a connector 5, thereby ensuring that the majority of the lower edges of the walls of the members 2 and 3 will bear upon the surface on which such members rest. The notches preferably are formed in all of the side and end walls of the platform member 2 and in the side and end walls 13, 13 a of the riser members.

[0033] The length of the platform and riser members may be uniform as is shown in FIGS. 1 and 2. However, the length of the riser members could be shorter than that of the platform members as is shown in FIG. 3. If the riser members are shorter than the platform members, the riser members may be positioned at either end of a stack of platform members or at the center thereof. It thus is possible to provide a ramp which has a portion of its width smoothly inclined and another portion of its width in stair-step form.

[0034]FIG. 2 discloses a ramp wherein a riser member 3 is in position to be placed atop the uppermost platform member 2. If it is desired to provide a horizontal surface at the upper end of the uppermost, or any other upper platform member, the riser member simply need not be applied to the upper end of a selected stack.

[0035] The disclosed embodiment is representative of a presently preferred form of the invention, but is intended to be illustrative rather than definitive thereof. The invention is defined in the claims. 

I claim:
 1. A knockdown ramp construction comprising at least one platform member having substantially flat, parallel, top and bottom surfaces terminating at corresponding edges in a perpendicular wall; and a wedge-shaped riser member having a substantially flat lower surface and an inclined upper surface, said lower and upper surfaces being joined by a wall perpendicular to said lower surface and having a height corresponding substantially to that of said wall of said platform member, said upper surface of said riser member being inclined at such angle as to enable the top surface of said platform member and the upper surface of said rise member at its maximum height to be at substantially the same level when said walls of said members abut one another.
 2. The construction according to claim 1 wherein said platform member has selected length and width dimensions and wherein said riser member has a width dimension corresponding substantially to the width dimension of said platform member.
 3. The construction according to claim 2 wherein said riser member has a length dimension different from the length dimension of said platform member.
 4. The construction according to claim 3 wherein the length dimension of said riser member is less than that of said platform member.
 5. The construction according to claim 1 including connector means removably connecting said wall of said platform member to said wall of said riser member.
 6. The construction according to claim 5 wherein said connector means comprises a base supporting at least two spaced apart, upstanding retainers, said retainers being spaced apart a distance sufficient to enable two walls of said base member and said riser member to be accommodated between said retainers when said two walls abut one another.
 7. The connector means according to claim 6 including two pairs of said retainers supported by said base.
 8. The construction according to claim 6 wherein said connector means has a selected thickness and wherein the walls of said platform member and said riser member are notched at their lower surface to accommodate said base of said connector means.
 9. A knockdown ramp construction comprising a plurality of identical platform members vertically stacked one upon another, each of said platform members having substantially flat, parallel, top and bottom surfaces terminating at corresponding edges in a perpendicular wall, the number of said platform members being sufficient to enable a plurality of stacks of said platform members to be arranged side-by-side, the number of said platform members in each adjacent stack being different by one whereby one of said adjacent stacks has a height greater than that of an adjacent stack; and a wedge-shaped riser member atop the uppermost platform member of the shorter of said adjacent stacks, said riser member having a substantially flat lower surface and an inclined upper surface, said lower and upper surfaces of said riser member being joined by a wall perpendicular to said lower surface of said riser member and having a height corresponding substantially to that of said wall of the uppermost platform member of the adjacent stack, said upper surface of said riser member being inclined at such angle as to enable said top surface and said upper surface to be at substantially the same level when said walls of said members abut one another.
 10. The construction according to claim 9 including coupling means interconnecting vertically adjacent ones of said platform members for preventing relative horizontal movement therebetween.
 11. The construction according to claim 10 wherein said coupling means comprises at least one pair of aligned sockets in the uppermost and adjacent lower platform members and a coupling accommodated in both sockets of said pair thereby inhibiting relative movement of said uppermost and adjacent lower platform members transversely of one another.
 12. The construction according to claim 9 including connector means removably connecting said perpendicular wall of said adjacent lowermost platform members thereby inhibiting relative movement of said adjacent stacks.
 13. The construction according to claim 9 wherein said connector means comprises a base supporting at least one pair of upstanding retainers, said retainers being spaced apart a distance corresponding substantially to the combined thickness of two of said perpendicular walls.
 14. A knockdown ramp formed from a plurality of uniform height platform members each of which is quadrangular and has flat upper and lower surfaces joined at their opposite edges by a vertical wall, said platform members being arranged to form a plurality of stacks adjacent one another with the number of platform numbers in each stack thereof in one direction of said ramp being one fewer than the number of platform members in the adjacent stack, the arrangement of said stacks being such that the adjacent stacks are in stair-step relation; a wedge-shaped riser member having a substantially flat lower surface and an inclined upper surface rising uniformly from one side edge to the opposite side edge of such riser member at such inclination that the height of said riser member at said opposite edge thereof corresponds to that of the adjacent platform member; first coupling means coupling vertically adjacent platform members together to prevent lateral movement relative to one another; and second coupling means connecting each riser member to the underlying platform member to prevent lateral movement of each said riser member relative to the underlying platform member.
 15. The ramp according to claim 14 wherein said first coupling means and said second coupling means correspond to one another.
 16. The ramp according to claim 15 wherein each of said coupling means comprises a pair of vertically aligned sockets in vertically adjacent ones of said members and an insert snugly accommodated in each of the sockets of said pair of sockets.
 17. The ramp according to claim 14 wherein each stack of said platform members has a lowermost platform member, and connector means connecting each of said adjacent lowermost platform members to one another to prevent lateral relative movement in a direction to separate said adjacent lowermost platform members from one another.
 18. The ramp according to claim 17 wherein said connector means comprises a base supporting at least one pair of upstanding fingers spaced from one another a distance corresponding substantially to the combined thickness of said vertical walls of two of said lowermost platform members.
 19. The ramp according to claim 14 including one of said riser members at that end of said ramp which is shorter in height, said one of said riser members having its vertical wall abutting the vertical wall of the adjacent lowermost platform member, and wherein said abutting vertical walls are maintained in abutting relation by said connector means.
 20. The ramp according to claim 14 including one of said riser members at that end of said ramp which is greater in height. 